Evening Primrose (Oenothera biennis)
Family: Onagraceae family
Common names: Sun Drop, King’s cure all, Night willow herb, Fever plant, German rampion, and Scabish.
Evening Primrose Oil is used in the following Wildcrafted Herbal Products:
Evening primrose (Oenothera biennis) has served as both food and medicine at previous times throughout history, often for upset stomach and respiratory infections. Native Americans ate the boiled, nutty-flavoured root, and used leaf poultices from the plant for bruises and haemorrhoids. European settlers took the root back to England and Germany, where it was introduced as food and became known as German rampion because it grew as a crawling vine (UMM).
Traditional / Historical Uses: Astringent and sedative. The drug extracted from this plant, has been tested in various directions, and has been employed with success in the treatment of gastro-intestinal disorders of a functional origin, asthma and whooping cough (Grieve, 1977).
According to Malcolm Stuart (1979) its uses include: Antispasmodic; nutritive; demulcent; weak astringent; vulnerary; anti-coagulent.
It may be applied externally as a poultice or in ointments in the treatment of minor wounds or skin eruptions, and used internally for coughs, colds, gastric irritation and intestinal spasm. A direct effect on the liver is suspected. Young roots can be boiled or pickled, and can be eaten hot or cold; all parts of the plant are edible.
The essential oil of the Evening primrose seed is primarily used to relieve itchiness associated with skin conditions such as eczema, and to ease breast tenderness from premenstrual syndrome (PMS) or other causes (UMM).
It is considered to be potentially useful for the treatment of many conditions including:
- Allergies, particularly skin rash or hives
- Eczema, including redness and scaling in addition to itching
- PMS, including mood swings and bloating in addition to breast tenderness
- Arthritis, primarily rheumatoid
- Dry eyes, from, for example, Sjogren's syndrome (a condition with symptoms of dry eyes, dry mouth, and, often, arthritis)
- Peripheral Neuropathy, a nerve condition experienced as numbness, tingling, pain, burning, or lack of sensation in the feet and/or legs, from Diabetes
- Menopausal symptoms. Although evening primrose oil has gained some popularity for treating hot flashes, the research to date has not confirmed that GLA or evening primrose oil is beneficial for these symptoms. However, there are individual women who report improvement; therefore, it may be worthwhile to talk to your doctor about whether it is safe for you to try evening primrose oil or another form of GLA supplements to alleviate hot flashes.
- Weight loss, particularly if you have a family history of obesity
- Alcoholism; evening primrose oil may help lessen cravings for alcohol and prevent liver damage. More research is needed in this area.
Other conditions for which evening primrose oil is currently under scientific investigation and may prove beneficial include: breast cancer, heart disease, high cholesterol, attention deficit/hyperactivity disorder, stomach ulcers, and inflammatory bowel disease (such as ulcerative colitis) (UMM).
Other indications include:
- Type 1 diabetes
- Type 2 diabetes
- Fibrocystic breast disease
- Osteoporosis (in combination with fish oil)
- Premenstrual syndrome (PMS)
- Rheumatoid arthritis
- Skin ulcers
It is also of use in dyspepsia, torpor of the liver, and in certain female complaints, such as pelvic fullness (Grieve, 1977).
Description: Biennial, or occasionally annual, producing, on thick yellowish conical root, compressed rosette of obtuse basal leaves to 60 cm diameter, from which arise much-branched reddish, rough stems to 1.25 m bearing alternate, lanceolate to ovate, entire, shortly periolate leaves 4 cm long (Stuart, 1979).
Growth Habit: A circle of leaves grows close to the ground around evening primrose stems after the first year it is planted. Flowers bloom after sunset, June through September (in the northern hemisphere), or on overcast days during the second year. Stems are branched, with alternate leaves (which means that the leaves grow on both sides of the stem at alternating levels) (UMM).
Grieve (1977) states: “The root is biennial, fusiform and fibrous, yellowish on the outside and white within. The first year, many obtuse leaves are produced, which spread flat on the ground. From among these in the second year, the more or less hairy stems arise and grow to a height of 3 or 4 feet. The later leaves are 3 to 5 inches long, 1 inch or more wide, pointed, with nearly entire margins and covered with short hairs. The flowers are produced all along the stalks, on axillary branches and in a terminating spike, often leafy at the base. The uppermost flowers come out first in June. The stalks keep continually advancing in height, and there is a constant succession of flowers till late in the autumn, making this one of the showiest of our hardy garden plants, if placed in large masses. The flowers are of a fine, yellow colour, large and delicately fragrant, and usually open between six and seven o'clock in the evening, hence the name of Evening Primrose.”
The roots of the Evening Primrose are eaten in some countries in the spring, and the French often use it for garnishing salads (Grieve, 1977).
Constituents of Evening Primrose
Evening Primrose Oil (Essential oil) is extracted from the seeds and prepared as medicine using a chemical called hexane. The seeds contain up to 25% essential fatty acids including linoleic acid (LA) and gamma-linolenic acid (GLA). Both LA and GLA belong to the omega-6 family of fatty acids (UMM).
The main active ingredient in evening primrose oil is gamma-linolenic acid (GLA). Ingredients include: palmitic and oleic acid, beta-sitosterol, and atrienoic acid.
Scientists at the Institute for Pharmaceutical Biology, in Basel, Switzerland, have recently identified highly active anti-inflammatory triterpenoidal esters in cold-pressed evening primrose oil. These compounds may contribute to the anti-inflammatory and anti-allergic properties of EPO, which had been up to now ascribed solely to the high content in GLA.
The American Herbal Products Association (AHPA) gives EPO a class 1 safety rating, which indicates that it is safe with appropriate use. Reported side effects are rare and mild, and include nausea, stomach pain, and headache. Stomach pain and loose stools may be indications that the dosage is too high (UMM).
Omega-6 supplements, including GLA and EPO, should not be used if you have a seizure disorder because there have been reports of these supplements inducing seizures (UMM).